docs(harder-bigger-bolder-stronger): correct grammar

subjects/harder-bigger-bolder-stronger/README.md

@@ -2,27 +2,26 @@
 
 ### Instructions
 
-Being stuck at home, bored, desperate and coming up with a lot of weird ideas, a friend asks you to develop a tool to measure his ocular skills: one of those [Monoyer charts](https://en.wikipedia.org/wiki/Monoyer_chart) that ophthalmologists use.
+Being stuck at home, bored, desperate and coming up with a lot of weird ideas, a friend asks you to develop a tool to measure his ocular skills. One of those [Monoyer charts](https://en.wikipedia.org/wiki/Monoyer_chart) that ophthalmologists use.
 
-Generate a board where each new letter is harder, bigger, bolder and stronger!
+Generate a board where each new letter is harder, bigger, bolder and stronger.
 
-Write the function `generateLetters` which creates 120 `div`, each containing a letter randomly picked through the **uppercase** alphabet, and whose style properties have to be increased:
-
-- each letter `font-size` has to grow from `11` to `130` pixels
-- `font-weight` has to be `300` for the first third of the letters, `400` for the second third, and `600` for the last third
+Write the function `generateLetters` which creates 120 `div` elements, each containing a letter randomly picked through the **uppercase** alphabet, and whose style properties have to be increased:
+- each letter's `font-size` has to grow from `11` to `130` pixels.
+- `font-weight` has to be `300` for the first third of the letters, `400` for the second third, and `600` for the last third.
 
 ### Files
 
-You only need to create & submit the JS file `harder-bigger-bolder-stronger.js` ; we're providing you the following file to download (click right and save link) & test locally:
+You only need to create & submit the JS file `harder-bigger-bolder-stronger.js`. We're providing you the following file to download and test locally:
 
 - the HTML file [harder-bigger-bolder-stronger.html](./harder-bigger-bolder-stronger.html) to open in the browser, which includes:
 
-  - the JS script running some code, and which will also allow to run yours
-  - some CSS pre-styled classes: feel free to use those as they are, or modify them
+  - the JS script running some code, and which will enable you to run yours.
+  - some CSS pre-styled classes: feel free to use those as they are, or modify them.
 
 ### Notions
 
-- [`createElement()`](https://developer.mozilla.org/en-US/docs/Web/API/Document/createElement)
-- [`append()`](https://developer.mozilla.org/en-US/docs/Web/API/ParentNode/append)
-- [`style`](https://developer.mozilla.org/en-US/docs/Web/API/ElementCSSInlineStyle/style)
-- [`textContent`](https://developer.mozilla.org/en-US/docs/Web/API/Node/textContent)
+- [createElement](https://developer.mozilla.org/en-US/docs/Web/API/Document/createElement)
+- [append](https://developer.mozilla.org/en-US/docs/Web/API/ParentNode/append)
+- [style](https://developer.mozilla.org/en-US/docs/Web/API/ElementCSSInlineStyle/style)
+- [textContent](https://developer.mozilla.org/en-US/docs/Web/API/Node/textContent)